As the Heartbleed bug fallout continues, McAfee is rolling out a free tool to help users detect how susceptible they are to its potentially dangerous impact. Heartbleed is a vulnerability in OpenSSL that has placed millions of Internet users’ personal information at risk.

Specifically, researchers estimate that Heartbleed could affect up to two-thirds of all Web sites. It works by exploiting a vulnerability in the popular OpenSSL encryption that protects usernames, passwords, credit and debit card numbers, and other personal information.

According to McAfee, this flaw in the SSL code could allow an attacker to gain access to system memory. Once that system memory is breached it could allow attackers to steal sensitive information or tap into personal communications. The security software firm said consumers should make a list of which sites they use that are affected and, after the sites are patched, change their account passwords.

Using Heartbleed Checker

“It’s important that users first check to make sure the Web sites they frequent are updated before changing their passwords,” said Gary Davis, vice president of consumer marketing at McAfee, part of Security. “In the wake of confusing information floating around, our tool makes it easy for consumers to quickly access the information they need. Armed with this information, consumers can decide when it is time to change their passwords and regain confidence in a safe Web surfing experience.”

Here’s how it works: Consumers can enter the Web site domains into the Heartbleed Checker tool. The results will reveal if that Web site has been affected by Heartbleed. It does this by checking whether or not the sites have been upgraded to the version of OpenSSL that is not susceptible to the bug.

Of course, it may not be as easy as that in the end. Web collaboration company Meldium has rooted out a new bug that affects servers already patched for Heartbleed. It’s appropriately called “Reverse Heartbleed.” The firm said the mitigation steps are the same as for the regular Heartbleed attack: don't use vulnerable versions of OpenSSL. Meldium has launched a Reverse Heartbleed tester.

Difficult to Fully Remediate

We caught up with Tim Erlin, director of IT security and risk strategy at Tripwire, to get his take this ongoing story. He told us, in reality, the severity of the Heartbleed vulnerability isn’t about the vulnerability itself. It’s about the popularity of OpenSSL.

“It’s the popularity and pervasiveness of the OpenSSL library that makes this vulnerability difficult to remediate fully,” Erlin said. “While popular web applications may be already patched, the myriad of appliances, embedded devices and network that may be vulnerable will take a lot longer to address. You can’t just disable the Internet for maintenance.”

Craig Young, security researcher at Tripwire, told us recovering from Heartbleed and restoring confidence in the Internet will be a long road, the effects of this bug are so widespread we’re going to see fall out for quite some time.” Young’s colleague, Tripwire security researcher Ken Westin, said it’s irresponsible to tell people to update all of their passwords everywhere, without providing context around the vulnerability.

“Changing your password on a site or service only mitigates Heartbleed risk if that service has patched their systems,” Young said. “If users change their passwords on a site or service that is still vulnerable, they may actually be putting themselves at greater risk as that new password is loaded into memory.”

All this is why McAfee is suggesting that consumers wait until after a site is free and clear of Heartbleed before changing passwords.